Looking for some advise on these few photos.....

Valvebounce

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Would it hurt to blow a little air towards sensor with air bulb? May be a topic for a new thread??
Hi Wm.
For a pretty definitive lesson on sensor cleaning have a look at this post.
Roger and lens rentals are well respected and they have gone to great lengths to earn that respect. There are tons of great info in most every post on the blog and a little humour to make reading it more fun!

Cheers, Graham.
 
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Rule of thumb for the right exposure time is 1/(crop factor*focal length) so for a 50 mm focal length on an APS-C camera, you shouldn't expose for longer than 1/(1.6*50) = 1/80 s. Any longer than that and you'll either need a tripod, great image stabilization or enormous luck to get a sharp image.
Hi Joules - I agree with your rule of thumb, I was just trying to keep it safe and simple for OP. Since I use crop bodies with crop factors of 1.5, 1.6 and 2.0 it's easier for me always use the 2X factor. Plus, I have read it argued that the smaller pixel pitch of crop bodies actually needs faster shutter speeds than the old rule of thumb to minimize blur. Final reason I tend to use the 2X factor is that I find it hard to do the math quickly in my head. If I've got a zoom lens set at 45 mm I can multiply by 2 in my head in an instant. To multiply by 1.6 isn't so fast. In truth though, if I know I'm going to face a situation where camera shake might be an issue I just grab a body with IBIS or a tripod.
 
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Joules

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Hi Joules - I agree with your rule of thumb, I was just trying to keep it safe and simple for OP. Since I use crop bodies with crop factors of 1.5, 1.6 and 2.0 it's easier for me always use the 2X factor. Plus, I have read it argued that the smaller pixel pitch of crop bodies actually needs faster shutter speeds than the old rule of thumb to minimize blur. Final reason I tend to use the 2X factor is that I find it hard to do the math quickly in my head. If I've got a zoom lens set at 45 mm I can multiply by 2 in my head in an instant. To multiply by 1.6 isn't so fast. In truth though, if I know I'm going to face a situation where camera shake might be an issue I just grab a body with IBIS or a tripod.
Hm, I had somehow completely skipped reading the second part of your post that already mentioned the rule of thumb. I totally agree that 2X for a modern APS-C body is more practical, both in accounting for the high megapixel counts and how to calculate it. Sorry for the redundancy in my post, I didn't mean to correct you are anything along those lines.
 
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Wm

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Jun 11, 2018
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update - sorry for lack of info. I saw some dust on mirror and used air bulb to blow off. I had taken a picture, the one I attached right above before hand ( white blank paper). I then put camera in manual clean mode and blew some more air. Released mirror and took another test shot and it appeared the same as the 1st shot - no change. So I assumed the "dirt" is on the sensor. Yes / No ?? Also, the magnifier I have is 7x. Is that enough to see dirt on sensor? Just following The Dust Patrol - on YouTube after looking at the link from above.
 
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Joules

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Are we even certain there is dirt/dust on the sensor?

Shooting against a bright, even background like a clear or grey sky with a narrow aperture is one way to make spots from dust on the sensor more apparent.

Also don't mess with dust on the mirror. It should not impact any property of the camera and if you touch the mirror with anything, odds of damaging the silver coating are pretty high I think.
 
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Wm

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Jun 11, 2018
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ok, so here's one more shot from outside. iOS 100, f22, manual focus. If you magnify the image a few times there is actually a few small rings that show and some other "something".... I dont know what any of these are or means. Very much a beginner and was just trying to figure out what the circles showing up in the 1st church picture are form. Tks
spots2.JPG
 
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JPAZ

If only I knew what I was doing.....
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ok, so here's one more shot from outside. iOS 100, f22, manual focus. If you magnify the image a few times there is actually a few small rings that show and some other "something".... I dont know what any of these are or means. Very much a beginner and was just trying to figure out what the circles showing up in the 1st church picture are form. Tks
View attachment 199296
IMHO, a blower can be helpful but I suspect you need to clean the sensor. You have two options: Take it to a reputable shop and have them do it; or, do it yourself. I know that sounds a bit scary but it really is not that difficult, with the right tools. Look at a few videos and get some appropriate swabs, a magnifier and the right fluid. Either way, I think that a sensor clean would help this issue.
 
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Joules

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Doesn't look dusty to me though. Maybe I just have a larger tolerance but my sensor looks worse than that :LOL:

I also have a hard time believing the bright dots in the church image are from dust. Certainly haven't seen sections of my images getting brightened from dust yet.

I have had accidents were my mouse went crazy and only after exporting the images I noticed streaks of brightness from lightroom brush in places where they shouldn't be. That's why that was my first guess.

Pretty weird, but unless it shows up in other images than the church one, I wouldn't worry about it.
 
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Wm

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Jun 11, 2018
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so there was one camera store left in my area and I believe they no longer sell or work on equipment. Anyhow, ive had issues with them before. I have carepak w/ canon so I decided to send it in for a cleaning. Getting it all ready led me to my paperwork and I had forgotten this - when the camera was new, i had to send it in for "spots" , twice.... I dont ofter shoot at a high f stop and im kinda new at post processing so I guess it hasn't been an issue.... just brings back bad memories having been the carepak route before. oh well.... off it went.
 
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